ANSWER 96
The history shows a progressive condition over at least 6 months. It is often difficult to be
sure of the exact length of history when a symptom such as breathlessness has an insidi-
ous onset. A few possibilities are raised by the details of the history. There is a history of
asthma but the absence of wheezing or obstruction on the respiratory function tests rule
that out. An occupational history is always important in lung disease but probably not
here. Occupational asthma can be associated with the printing trade but not a restrictive
problem as shown here. The findings on examination fit with a restrictive problem with
limited expansion and the crackles caused by re-opening of airways closing during expir-
ation because of stiff lungs and low lung volumes.
The respiratory function tests show a mild restrictive ventilatory defect with reduced FEV 1
and FVC but a slightly high ratio, suggesting stiff lungs or chest wall. Further tests such
as transfer factor would be expected to be reduced in the presence of pulmonary fibrosis.
The chest X-ray shows small lung fields and nodular and reticular shadowing most marked in
mid and lower zones. The high-resolution CT scan shows widespread fibrotic change with sub-
pleural cyst formation. These changes are compatible with diffuse pulmonary fibrosis (fibro-
sing alveolitis). In talking about fibrosis of the lungs it is important to differentiate diffuse fine
pulmonary fibrosis, as in this case, and localized pulmonary fibrosis as a result of scarring
after an acute inflammatory condition such as pneumonia. The distribution and the pattern of
the changes on the CT scan are important in determining the diagnosis and the likelihood of
response to treatment in pulmonary fibrosis. Diffuse pulmonary fibrosis can be associated with
conditions such as rheumatoid arthritis and can be induced by inhaled dusts or ingested drugs.
None of these seem likely here making this likely to be idiopathic pulmonary fibrosis(IPF).
There is a rare familial form so the father’s illness might be relevant. The common type of IPF
is usual interstitial pneumonia (UIP) with a subpleural distribution on the CT scan as shown
here. In association with connective tissue disease there may be a more widespread patchy pat-
tern of non-specific interstitial pneumonitis (NSIP). The appearance of ‘ground glass’ shadow-
ing on the high-resolution CT is associated with an active cellular alveolitis and the greater
likelihood of response to treatment. NSIP also has a better response rate than UIP.
Further investigations consist of a search for a cause or associated conditions and a deci-
sion whether a lung biopsy is warranted. Bronchoscopic biopsies are too small to be rep-
resentative or useful in this situation, and a video-assisted thoracoscopic biopsy would be
the usual procedure. It would usually be appropriate to obtain histology of the lung in
someone of this age.
Treatment consists of low- to moderate-dose corticosteroids with or without an immunosup-
pressant such as azathioprine continued for several months to look for an effect, but the
results are poor in UIP and it is important not to cause more harm than benefit from treatment
with prolonged steroids and immunosuppressants. There is some evidence that anti-oxidants
such as acetylcysteine improve the outlook and these may be combined with the steroids and
azathioprine. In a patient of this age, lung transplantation might be a consideration as the dis-
ease progresses. Progression rates are variable and an acute aggressive form with death in
6 months can occur. More common in UIP is steady progression over a few years.
- Diffuse pulmonary fibrosis has a range of causes relevant to management.
- Ineffective treatment may produce serious side-effects without significant benefit.